Modular electronics components require functionally correct packaging which enables different setting and operating functions and can be assembled in a manner which is as simple as possible but yet safe and reliable. With the trend of increasing control and automation of processes, in particular in the industrial sector, and simultaneous decentralization of electronics directly into the process as well as the miniaturization of electronics assemblies to form compact devices which are easy to install, suitable electronics housings are therefore increasingly required, wherein, in general, the connection technology is then also integrated in the housing. In this case, the individual electronic devices can, in general, be fitted directly on a mounting rail and preferably connected to one another and to a controller by way of a bus system.
In this connection, depending on the application case, there is a multitude of different electronic devices and housing forms which differ in terms of their size, their design and their function. All of said electronic devices have the common feature that electronic assemblies, usually in the form of printed circuit boards, are arranged in their interior, said electronic assemblies being protected from touching contact and dirt by the electronics housing. Housings such as this are usually of modular design, with the result that it is quickly and easily possible to insert or replace a printed circuit board and hence to adapt the electronic device to different requirements.
The housings often include a housing upper part and a housing lower part. The housing upper part has connections for electrical lines, the connections are connected to the housing lower part by way of plug contacts, and the housing lower part produces the connection to a bus system. The individual housings are in this case designed such that a plurality of housings can be latched on a mounting rail one next to the other, with the result that a plurality of housings together form a housing block. In this case, the individual adjacent housings or the individual adjacent electronic devices can preferably make electrical contact with one another.
Such housings or electronic devices are fastened to the mounting rail owing to a locking element being arranged in the housing lower side, wherein the locking element is latched to the mounting rail when the housing is positioned on the mounting rail. In order to release the housing and hence also the electronic device from the mounting rail, the above-described latching must be released, for which purpose the locking element, which is usually acted upon by a spring, must be pushed back against a spring force.
For this purpose, EP 0 976 310 B1 describes an electrical device having a housing which is composed of two identical housing shells which are assembled in a manner mirror-inverted with respect to one another, wherein the housing is provided with a snap fastening for snapping onto a mounting rail, and wherein the snap fastening is realized by means of two spring latching hooks, each of which is integrated into in each case one housing shell.
Electronics housings which are of modular design and are based on half-shell technology, that is to say which consist of at least two housing parts which are latched with respect to one another, have the disadvantage that no pre-centering or guidance to one another is provided, with the result that they must be fitted freehand.